class Dog(object):
    def work(self):
        print('指哪打哪...')

class ArmyDog(Dog):
    def work(self):
        print('追击敌人...')

class DrugDog(Dog):
    def work(self):
        print('追查毒品...')

class Person(object):
    def work_with_dog(self,dog):
        dog.work()

ad=ArmyDog()
dd=DrugDog()

dq=Person()
dq.work_with_dog(ad)
dq.work_with_dog(dd)

print('1')